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It was hypothesized that faster cardiorespiratory kinetics during exercise are associated with higher orthostatic tolerance. Cardiorespiratory kinetics of 14 healthy male subjects (30 [+ or -] 4 years, 179 [+ or -] 8 cm, 79 [+ or -] 8 kg) were tested on a cycle ergometer during exercise with changing work rates of 30 and 80 W. Pulmonary oxygen uptake ([??][O.sub.2pulm]) was measured breath-by-breath and heart rate (HR), mean arterial blood pressure (MAP), and total peripheral resistance (TPR) were measured beat-to-beat. Muscular oxygen uptake ([??][O.sub.2musc]) was estimated from HR and [??][O.sub.2pulm]. Kinetic parameters were determined by time-series analysis, using cross-correlation functions ([CCF.sub.max](x)) between the parameter and the work rate. Cardiovascular regulations of MAP, HR, and TPR during orthostatic stress were measured beat-to-beat on a tilt seat. Changes between the minima and maxima during the 6[degrees] head-down tilt and the 90[degrees] head-up tilt positions were calculated for each parameter ([[DELTA].sub.tilt-up]). [CCF.sub.max] ([??][O.sub.2musc]) correlated significantly with [DELTA][TPR.sub.tilt-up] (r = 0.790, p [less than or equal to] 0.001). [CCF.sub.max](HR) was significantly correlated with [DELTA][HR.sub.tilt-up] (r = -0.705, p = 0.002) and the amplitude in HR from 30 to 80 W ([r.sub.SP] = -0.574, p = 0.016). The observed correlations between cardiorespiratory regulation in response to exercise and orthostatic stress during rest might allow for a more differential analysis of the underlying mechanisms of orthostatic intolerance in, for example, patient groups. Key words: cardiovascular regulation, orthostatic stress, cardiorespiratory kinetics, tilting experiments, exercise, physical fitness, orthostatic tolerance. Nous avons pose l'hypothese selon laquelle la cinetique cardiorespiratoire plus rapide pendant l'exercice physique est associee avec une plus grande tolerance orthostatique. Nous avons etudie la cinetique cardiorespiratoire chez 14 sujets de sexe masculin en bonne sante (30 [+ or -] 4 ans, 179 [+ or -] 8 cm, 79 [+ or -] 8 kg) a l'aide d'une bicyclette ergometrique pendant un exercice physique avec des rythmes de travail variables de 30 et 80 W. Nous avons mesure le taux d'absorption de l'oxygene par les poumons ([??][O.sub.2pulm]) respiration par respiration et la frequence cardiaque (FC), la tension arterielle moyenne (TAM) et la resistance peripherique totale (RPT) battement par battement. Nous avons estime le taux d'absorption de l'oxygene par les muscles ([??][O.sub.2musc]) a partir de la FC et de la [??][O.sub.2pulm]. Nous avons etabli les parametres cinetiques par une analyse chronologique a l'aide de fonctions de correlation croisees ([FCC.sub.max](x)) entre le parametre et le rythme de travail. Nous avons mesure la regulation cardiovasculaire de la TAM, de la FC et de la RPT pendant un stress orthostatique battement par battement sur un siege basculant. Nous avons calcule les variations de chacun des parametres entre les minimums et les maximums pendant les positions de basculement tete vers le bas de 6[degrees] et basculement tete vers le haut de 90[degrees] (Abasc-haut). La [FCC.sub.max] ([??][O.sub.2musc]) etait nettement proportionnelle a la [DELTA][RPT.sub.basc-haut] (r = 0,790; p [less than or equal to] 0,001). La [FCC.sub.max](FC) etait nettement inversement proportionnelle a la [DELTA][FC.sub.basc-haut] (r = -0,705; p = 0,002), ainsi qu'a l'amplitude de la FC de 30 a 80 W ([r.sub.SP] = -0,574; p = 0,016). Les correlations observees entre la regulation cardiorespiratoire en reaction a l'exercice physique et l'orthostatisme au repos pourraient permettre de proceder a une etude plus differentielle des modes d'action sous-jacents de l'intolerance a l'orthostatisme, par exemple aupres de groupes de patients. [Traduit par la Redaction] Mots-cles : regulation cardiovasculaire, stress orthostatique, cinetique cardiorespiratoire, experiences de basculement, exercice physique, forme physique, tolerance orthostatique., Introduction Tilting the human body in different positions during both rest and exercise provides an opportunity to investigate circulatory reflex responses and hemodynamic adjustments in response to orthostatic stress (OS; [...]

This article discusses the evaluation of ventricular function in Fontan patients, who have a single right ventricle (sRV). The study examines whether total isovolumic time (t-IVT), a marker of left ventricular systolic-diastolic interaction, can be used as a marker of sRV function. The researchers performed a retrospective analysis of echocardiography and cardiac magnetic resonance studies of 47 Fontan patients and found that t-IVT correlated closely with sRV ejection fraction (sRV-EF), suggesting that it can be a useful marker for monitoring systolic function in these patients. The study also suggests that global longitudinal strain (GLS) is a sensitive parameter for detecting changes in sRV function. [Extracted from the article]

KJ Weidner,1,* I El-Battrawy,1,2,* M Behnes,1 K Schramm,1 C Fastner,1,2 J Kuschyk,1 U Hoffmann,1,2 U Ansari,1 M Borggrefe,1,2 I Akin1,2 1First Department of Medicine, University Medical Centre Mannheim, Faculty of Medicine Mannheim, University of Heidelberg, 2DZHK (German Center for Cardiovascular Research), Partner Site, Heidelberg, Mannheim, Germany *These authors contributed equally to this work Background: Previous studies revealed that patients with Takotsubo cardiomyopathy (TTC) have a higher mortality rate than the general population. It is still unclear whether sex differences may influence long-term prognosis of TTC patients. The purpose of this study was to determine whether sex differences do influence the short- and long-term outcomes of TTC. Methods and results: A total of 114 patients with TTC were admitted to the University Medical Centre Mannheim from January 2003 to September 2015 and entered into the TTC database of the University Medical Centre Mannheim, and retrospectively analyzed. Patients were diagnosed by the Mayo Clinic criteria. All-cause mortality over mean follow-up of 1,529±1,121 days was revealed. Significantly more male patients died within long-term follow-up compared to female TTC patients (log-rank test; P=0.01). Most males died of noncardiac causes. In multivariate Cox regression analysis, the male sex (P=0.02, hazard ratio [HR] 2.8, 95% CI 1.1–7.2), the ejection fraction ≤35% (P=0.01, HR 3.3, 95% CI 1.2–9.2) and glomerular filtration rate